Thanks for the advice.
I have decided to try a simple multi-cache to get the 'feel for it' first.
I'll work on the Trust site one after I see how the first one is progressing (and hear some feedback from users). As you say - I am sure the reviewers can help.
Well, just found out the first one has been published. (Biggin on the Bump)
Combination of a historic airfield, good pub, some interesting street furniture, a circular ByWay walk and a nice view. Phew! Setting it up was a nice way to spend a sunny Saturday. :-)
Thanks for your help.
Hope it gives enjoyment to others!